Method and apparatus for scouring raw loose wool

ABSTRACT

A METHOD FOR WASHING AND SCOURING LOOSE WOOL WHICH HAS BEEN SUBJECTED TO A PRELIMINARY WASHIG CARRIED OUT IN A FLOATING DOWN TYPE WASHING BATH TO SEPARATE AT LEAST A PART OF OIL AND DIRT FROM THE LOOSE, WOOL, WHICH METHOD COMPRISES CONVEYING LOOSE WOOL IN A LAYER PLACED BETWEEN TWO NET CONVEYORS MOUNTED IN PARALLEL AND MOVABLE ALONG A GIVEN PATH THROUGH A LIQUOR SCOURING BATH, SAID PATH BEING PREFERABLY AT A LEVEL OF ABOUT 40-60 MM. BENEATH THE LIQUID SURFACE, SUPPLYING SAID BATH WITH SCOURING LIQUID UNDER SUBSTANTIALLY NO PRESSURE FROM A SCOURING LIQUID FEEDING DEVICE WHICH IS POSITIONED ABOVE SAID PATH AND DRAWING THE SCOURING LIQUID BY AN UPTAKE SUCTION MEANS POSITIONED BELOW THE SAID PATH, WHEREBY   STEADY AND GENTLE DIFFUSION FLOW PASSES DOWNWARDLY ENTIRELY THROUGH THE FIBER LAYER. AN APPARATUS SUITABLE FOR PERFORMING THE ABOVE MENTIONED METHOD HAS BEEN ALSO PROPOSED.

Jan. 2, 1973 I MASAQ WATANABE ETAL 3,708,262

' METHOD AND APPARATUS FOR SCOURING RAW LOOSE WOOL Filed 001;. 15, 1970V 4 4 Sheets-Sheet 'Fla/ INVENTQRS M45344 W 74 45! Jan. 2, 1973 MASAOWATANABE ETAL 3,708,262

METHOD AND APPARATUS FOR scounme RAW LOOSE WOOL 4 Sheets-Sheet 2 FiledOct. 15, 1970 INVENTORS MAJ/M MIDI/V455 a My mw mm A ORNEYS 1973 MASAOWATANABE ET AL 3,708,262

METHOD AND APPARATUS FOR SCOURING RAW LOOSE WOOL FiledOct. 15, 1970 4Sheets-Sheet 5 FIG. 4

INVENTORS Jan. 2, 1973 MASAO WATANABE ET L' 3,708,262

METHOD AND APPARATUS FOR SCOURING RAW LOOSE WOOL 4 Sheets-Sheet 4 FiledOct. 15, 1970 & x V 3 O o 0 oo 0 0 o 000 Q Dw 0 4 Q a n WU MU ooed. v Qw M- Q D W5 w? J Wd% 0% My K United States Patent Ofice 3,708,262Patented Jan. 2, 1973 3,708,262 METHOD AND APPARATUS FOR SCOURING RAWLOOSE WOOL Masao Watanabe, Nishinomiya, and Hidekazu Mizoguchi and MakioHoshikawa, Kyoto, Japan, assignors to Kanegafuchi Boseki KabushikiKaisha, Tokyo, Japan Filed Oct. 15, 1970, Ser. No. 81,043 Claimsprion'ty, application Japan, Oct. 20, 1969, 44/ 83,693 Int. Cl. D01c3/00 US. Cl. 8-139 8 Claims ABSTRACT OF THE DISCLOSURE A method forwashing and scouring loose wool which has been subjected to apreliminary washing carried out in a floating down type washing bath toseparate at least a part of soil and dirt from the loose wool, whichmethod comprises conveying loose wool in a layer placed between two netconveyors mounted in parallel and movable along a given path through aliquor scouring bath, said path being preferably at a level of about40-60 mm. beneath the liquid surface, supplying said bath with scouringliquid under substantially no pressure from a scouring liquid feedingdevice which is positioned above said path and drawing the scouringliquid by an uptake suction means positioned below the said path,whereby steady and gentle diffusion flow passes downwardly entirelythrough the fiber layer. An apparatus suitable for performing the abovementioned method has been also proposed.

The present invention relates to an improvement in a method for washingand scouring loose raw wool and to an apparatus used therefor, moreparticularly, to a method and an apparatus for scouring loose wool,wherein the scouring liquid passes evenly through the fiber mass,whereby a homogeneous scouring effect is attained and felting of loosefibers can be prevented.

Heretofore, it has been known to wash and scour loose wool by conveyingit in a layer placed on a net conveyor or between two net conveyors,along a given path through a liquor bath and projecting onto the wool,while it travels along the path, jets of liquid such as water or washingliquor, extending transversely of the path of travel of the wool, fromabove to below. However, it has been very difiicult, in general, for theloose fiber to be formed into a lap having an even thickness, so thatthere is formed an uneven thick and thin lap on the net conveyor orbetween the two net conveyors. This fact has often led to the drawbackthat the scouring liquid passes unevenly through the lap, wherebyuniform scouring is hindered or the scouring effect is lowered. In orderto eliminate such drawback and to improve the scouring effect, there hasbeen proposed a method of applying a suction, from below, to the lapi.e., fiber layer, when jets of liquid are projected thereonto fromabove.

However, a method as described above comprising projecting or spraying ascouring liquid onto the wool and concurrently drawing the liquid bysuction from the opposite side results in the scouring effect beinglimited to narrow spots, even if it has an increased effect due to jetpressure, and further causes relative movement of the fiber between thenets, unless the fiber is compressed or nipped by a pair of press rolls.Thus such a conventional method has a drawback that the repeatedmovement gives rise to a felting phenomenon of the fiber mass, therebydegrading the quality of the fiber. Moreover, when the flow rate of thejet stream is too high, soil and dirt which have been precipitated atthe bottom of scouring bowl rise and float in the liquid undercirculation and not only contaminate the scouring liquid, but alsoinhibit the washing effect of raw wool.

In view of the above, the present invention provides an excellent methodfor scouring raw Wool and an apparatus suitable for conducting saidmethod, which can be advantageously carried out on an industrial scaleand which does not cause degradation in the quality of the fiber.

Thus, the principal object of this invention is to provide an effectivemethod for scouring raw loose wool by conveying it in a layer placedbetween two conveyor nets, wherein the scouring liquid passes evenlythrough the layer and homogeneous scouring is effected.

Another object of this invention is to avoid relative movement of fibersplaced between the two conveyor nets thereby preventing degradation infiber quality due to felting phenomenon of the fiber.

A further object of the invention is to provide a method for performinghomogeneous scouring by forming a fiber layer of a relatively lowapparent specific gravity, not too compressed, and thus permitting thescouring liquid to pass smoothly through the layer.

A still further object of the invention is to enhance theabove-described effective scouring, by separating from loose woolforeign matter e.g., soil and dirt, contained therein, immediately afterloosening the raw Wool and thereafter feeding the fiber in a homogeneouslayer to a scouring bowl.

An additional object of the invention is to provide a scouring apparatussuitable for accomplishing said method.

In order to attain the above objects, one of the essential features ofthe present invention resides in a method for washing and scouring loosewool, which comprises conveying raw loose wool from which at least apart of the soil and dirt has been separated beforehand by washing, in alayer placed between two net conveyors mounted in parallel and movablealong a given path through a liquor scouring bath, supplying said bathwith scouring liquid under substantially no pressure from a scouringliquid feeding device which is positioned above said path and drawingthe scouring liquid by an uptake suction means positioned below the saidpath, whereby diifusion flow of the scouring liquid occurs as it passesentirely through the fiber laver from above to below.

Another feature of the invention relates to an apparatus for performingthe said washing and scouring, characterized by comprising a scouringbowl containing a scouring liquid, a pair of endless net conveyorsmounted one above the other for conveying a continuous lap of raw loosewool placed therebetween along a path through the scouring liquid, saidpath being preferably at a level of 40-60 mm. beneaths the liquidsurface, a scouring liquid supply means of the overflow type positionedabove said path and an uptake suction means arranged below said path inthe liquid.

A further feature of the present invention is a method for washing andscouring raw loose wool which further comprises, in addition to theabove mentioned steps, a preliminary washing carried out prior to theabove mentioned steps, comprising letting raw loose wool fall into awashing bath, floating the wool down towards the rear of the bath by theaction of liquid flow, separating from the wool foreign matters such assoil and dirt contained therein through a perforated plate at the bottomof the liquid bath while the wool is travelling along the surface ofsaid plate, and forming the loose wool into a layer having a uniformthickness which is thereafter subjected to the subsequent method.

All other objects and features of the invention will become apparentfrom the description of. the specification hereinafter.

The present invention will be illustrated with reference to theaccompanying drawings:

FIG. 1 is a schematic side elevational view of a preferred embodiment ofthe apparatus of the present invention which is used for the preliminarywashing of loose wool prior to scouring;

FIG. 2 is a plan view corresponding to FIG. 1;

FIG. 3 is a schematic side elevational view of an em bodiment of theapparatus of the invention which is suitably used for the scouringmethod;

FIG. 4 is a plan view corresponding to FIG. 3; and

FIG. 5 is a side elevational view on an enlarged scale showing thewashing bath in FIG. 1.

In FIG. 1, the raw wool to be washed W is scatteringly supplied andfalls down through a hopper feeder H into a washing bath 1, whereforeign matter contained in the wool is separated. When the loose woolis fed into the hopper, a circulated washing liquid is jet-sprayedthrough the circulation pipes 3 while decreasing the water jet pressureby shelter plate 2, whereby the raw wool W is forcibly fed into thewashing bath 1 from the bottom of the hopper. Since the row wool W andthe washing liquid are successively fed into the bath 1, the raw wool Wflows slowly into the bath 1 and travels towards the rear of the bath,during which time the washing liquid is sprayed through a spray pipe 4which are arranged above the bath 1 thereby diffusing and floatingsmoothly the raw wool W and at the same time, separating from the woolsoil and dirt contained therein. The loose fiber floating in the washingliquid which has reached the rear end of the washing bath 1 is floatedover a baflie plate 5 and is moved onto an adjacent net conveyor 6 andis depositing thereon.

In this case it has been ascertained by the inventors throughexperiments that the most suitable ratio of the flow rate of the washingliquid to velocity of the net conveyor 6 is in a range of 2.5-3.5:1.

The loose Wool to be scoured thus deposited and piled on the netconveyor 6 forms a layer of a uniform thickness saturated with washingliquid.

As the conveyor 6 moves, the layer of wool is squeezed slightly by anintermediate press roll 7 into a uniform lap. A spray pipe 8 is providedfor preventing the fiber from winding around the intermediate roll 7.

The raw wool conveyed by the net conveyor 6 is subsequently transferredby a sponge roll 9 onto a feed net conveyor 10, and then is fed into thenip of squeeze roll 11 where it is squeezed under pressure. Thus theloose wool in a homogeneous layer W is subsequently transferred to thescouring bowl 18 without any unevenness by means of a delivery conveyor12.

The method of separating at least a part of the impurities from the rawwool in the washing bath 1 as above will be further explainedhereinafter in more detail.

In order to facilitate the charging of the raw wool through the hopper Hinto the washing bath 1 along with the circulated washing liquid and inview of the long path of fall, it is preferred to form the hopper wallinclined steeply so that the raw wool can slide down smoothly along theslope of wall. The charged wool is then pushed by the pressure of liquidsprayed from the pipes 3 and shifted to a gently inclined plane withliquid flow, while foreign matter such as soil and dirt contained in theraw wool falls to the bottom of the washing bath. The deposited amountis usually largest at the inlet portion and gradually decreases as thebaflle plate 5 is approached where it is smallest. For instance, therecould happen a case in which the height of the deposit is 60 mm. at theinlet portion and 20 mm. adjacent to the bafile plate after an eighthour run. In view of the above fact, the inventors have succeeded inimproving the washing effect by adopting a double bottom system for theWashing bath wherein as the upper bottom, a perforated plate 13 isemployed to permit only foreign matter to pass through the perforationsthereof and the foreign matter deposited on the lower bottom isdischarged intermittently by means of mud discharge valve 14.

On the other hand, when the capacity of the washing bath iscomparatively small, it is impossible to make the foreign matter depositcompletely because of the high circulation rate of the washing liquid.Accordingly, a further improvement of the washing effect is attainableby substituting a precipitation bath of a big capacity for the washingbath and installing subsidiary tank 16, as shown in FIG. 2, providedwith filters 17 and connected with the precipitation bath by conduitsand with the spray pipe 3 :by pipes 15 attached with a circulation pump.

As described before, the raw loose wool conveyed by the conveyor net 6is delivered by the sponge roll 9 and the feed net conveyor 10 to thesqueeze roll 11. After squeezing, it is fed into the scouring bowl bythe delivery conveyor 12 and thereafter subjected to scouring. Needlessto say, the construction and design may also be altered in such a mannerthat washing can be repeated on a successively installed conveyor netsimilar to the conveyor net 6, without used the sponge roll 9, feed net10, etc.

When soapy water is employed, the washing effect is more enhanced andgrease, soil and dirt can be removed.

Thus, the raw wool is washed sufliciently by a washing liquid andtransferred to the following scouring step. The method for separatingfrom raw wool at least a part of inpurities contained therein by Washingas described above is most effective and preferred as a preliminarywashmg.

In the present invention, however, a washing and scouring method of aconventional fork type may also be employed, as a preliminary washing.In that case, the washing bath which is shown in FIGS. 1 and 2 isreplaced with a fork type washing bowl.

The method for scouring raw wool which is the essential part of theinvention will be illustrated concretely hereinafter with reference toFIGS. 3 and 4.

Referring to FIGS. 3 and 4, in a scouring bowl 18, a pair of netconveyors 19 and 22 are mounted one above the other, and these conveyorscarry a layer of wool W washed previously in the preceding process andplaced between the net conveyors, along a path through scouring liquidin the bowl 18 and delivers the layer to squeeze rolls 31, 31 mounted atthe back or discharge end of the bowl 18. The path of the layer throughscouring liquid is preferably at a level of approximately 40-60 mm.beneath the liquid surface. Tension rolls 30 are arranged transverselyto the net conveyors under the wool holding part of the conveyor. Anoverflow type diffusion channel 25 for supplying the scouring liquid ispositioned above the path, in the liquid, of the wool layer. Uptakesuction means 28 for drawing scouring liquid are arranged under theabove mentioned path of the wool layer in the liquid. Said overflow typediffusion channel 25 is provided with the feeding pipe 26 encasedtherein having a slit 27 at its bottom. The scouring liquid fed outthrough the slit 27 into the diffusion channel 25 is flowed over theside wall thereof and falls down into the scouring bowl 18.

It is preferred that the position of the channel 25 is the same orslightly above the liquid level, and a plurality of the channels arearranged spaced apart an appropriate distance. Three diffusion channels25 are mounted in the apparatus shown in FIGS. 3 and 4, but the numberis non-limitative and may be determined appropriately depending on thelength of the net conveyors 19, 22 and period of the treatment time. Theuptake suction means 28 under the path of the wool layer through theliquid has the suction slit 29 at its bottom, so that the scouringliquid is sucked upwardly from below. This uptake suction means 28 ispreferably positioned below and midway between adjacent diffusionchannels, not right below the diffusion channel 25, whereby the liquidis permitted to permeate homogeneously through the wool layer over aWide range.

The number of the suction means 28 may be determined to conform to thenumber of the diffusion channels 25. The feeding pipe 26 and the suctionmeans 28 are connected with each other so that the scouring liquid maybe circulated. An example of the connected circulation route isillustrated in FIG. 4, wherein the subsidiary tank 32 is equipped at oneside of the scouring bowl 18 and the scouring liquid circulating throughthe bowl 18 and tank 32 is drawn by the suction means 28 and fed intothe subsidiary tank 32 through a pipe 34. The liquid in the subsidiarytank 32 is then fed into the diffusion channel 25 through the slit 27 ofthe feeding pipe 26. During the operation, grease and soil separatedfrom the raw wool layer W are gradually precipitated and deposit on thebottom of the subsidiary tank 32 as well as that of the souring bowl 18,and then are discharged outside by suitable means. In order to prevent adecrease of scouring ability due to an increase of grease contained inthe scouring liquid and to maintain a sufficient scouring ability, freshscouring liquid is successively supplied into the circulation route.

In the embodiment shown in FIG. 4, the feeding means 26 is a manifoldcomprising a main pipe 33 and branched pipes 33a, 33b, 33c; the lastsuction pipe 34a at the farthermost end of travelling layer isindependently connected to the subsidiary tank 32 and the other suctionpipes are connected by a feedback pipe 34 to the subsidiary tank 32. Thecirculation system to be employed in the present invention is notlimited to such a system as described above, but any other circulationsystem can be adopted at ones discretion,

In FIGS. 3 and 4, driving rolls 20, 23 drive the upper net conveyor 19and the lowest net conveyor 22 respectively, and guide rolls 21, 24 areprovided for the upper and lower net conveyor respectively. Thus thescouring of the homogeneous raw wool layer W which has been roughlywashed and then placed in the scouring bowl 18 is carried out bydiffusion and fiuidization of the liquid which is caused when thescouring liquid is flow over the diffusion channel 25 having the feedingmeans 26 near the water level in the bowl 18 and then the liquid isdrawn by the uptake suction means 28 from below. The overflow stream ispoured with substantially no pressure into the bath, which is differentfrom jet flow, so that the fiuidization is mainly caused only by suctionforce of the lower uptake suction means 28. Further, since the suctionmeans 28 is provided at its bottom with the slit 29, it is possible tocause a homogeneous flowing of liquid over a wide range of the bathwithout any localized flowing as occurs in the conventional arrangementin 'which a suction nozzle faces a jet nozzle.

It will be noted that by arranging alternately the suc tion means 28 andthe feeding means 26, scouring liquid flows in a slightly oblique streamwhich passes homogeneously and smoothly through wool layer.

As described above, in the present invention, since scouring is carriedout by means of a steady vertical flow of the scouring liquid, there iscaused substantially no relative movement of raw wool fiber beingconveyed, which prevents felting of the fiber mass. The thickness andapparent specific gravity of the raw wool placed between conveyor netsare preferably such that the scouring liquid is permitted to passsmoothly through the layer and accordingly, it is not necessary tocompress strongly the wool layer by and between conveyor nets, whereforit is possible to make the fiber under relatively free condition with aproper thickness.

The flowing stream which permeates through the raw wool W and is drawninto the suction means 28 is so gentle and steady that there is nopossibility for the impurities of the raw wool precipitated anddeposited on the bottom of the bowl to rise and float in the circulatingstream liquid, so that according to the present invention, an effectivescouring can be accomplished.

What is claimed is:

1. A method of scouring washed raw wool, utilizing upper and lower,opposed, net conveyor belts movable in parallel paths through a liquidscouring bath, said paths each including a substantially horizontallyextending portion submerged in said bath, and suction means disposed insaid bath below said horizontally extending portion of said lower belt,the method comprising the steps of:

placing loose raw wool between said belts to form a substantiallyuniform thickness, loose wool layer confined between said belts and thenmoving said belts through said bath so that said layer is moved throughand is submerged in said bath;

continuously feeding fresh scouring liquid to the upper portion of saidscouring liquid bath above said belts, the fresh scouring liquid beingunder atmospheric pressure and being distributed substantially uniformlyabove the substantially horizontally extending portions of said belts;

continuously drawing spent scouring liquid upwardly into said suctionmeans from the bottom of said bath in a region below the substantiallyhorizontally extending portions of said belts, and discharging saidspent scouring liquid from the bath, thereby to effect a substantiallyuniform, steady and gentle downward flow of the scouring liquid throughthe wool layer and the belts over substantially the entire length of thesubstantially horizontally extending portions of said belts.

2. A method as claimed in claim 1, wherein the raw loose wool has beenformed, in advance, into a layer having a substantially uniformthickness.

3. A method as claimed in claim 1, wherein the layer placed between twonet conveyors has a low apparent specific gravity.

4. A method according to claim 1, in which said substantiallyhorizontally extending portion of said layer is below the upper surfaceof said scouring liquid bath a distance in the range of from about 40mm. to about 60 mm.

5. A method according to claim 1, in which the fresh scouring liquid isfed into said scouring liquid bath by feeding the fresh scouring liquidinto open-topped receptacle means and overflowing the fresh scouringliquid from said receptacle means onto the upper surface of said bath.

6. A method according to claim 1, in which said spent scouring liquid isremoved from said scouring liquid bath from a series of zones spacedapart along substantially the entire length of said horizontallyextending portions of said belts.

7. A method according to claim 1, including the preliminary process ofwashing raw wool prior to placing same between said belts, comprisingthe steps of feeding References Cited loose raw wool downwardly into awashing bath, retain- UNITED STATES PATENTS ing the wool on a perforatemember at the bottom of the 2 183 142 12/1939 M k 8 139 washing bath andpassing the washing liquid through the 2724955 11/1955 1 2253 I Xperforate member, and then formlng the loose wool into 5 3205207 8/1965Poncelet a layer of uniform thickness.

8. A method according to claim 7, in which streams of washing liquid aredirected downwardly into the wash- MAYER WEINBLATT Primary Exammer ingbath thereby to force the wool toward the bottom 7 s CL 0f the bath. 10139 1; 44

